Dear Vince;
The pistons don't float. You need to look up 'full floating wrist pins'.
This term is used when the item has a bearing surface on both sides and moves (floats) freely etc. Flathead Ford V-8 rod bearings do this too.
The GMC is the only one one I know of that has 'full floaters' in there pistons/rods & It's because the pin is almost 1" in diameter (.990).
It doesn't really matter with the small pins.
Larry P. might have more info on this topic.
